1. Field of the Invention
This invention relates to ground fault circuit breakers with flat bus bars extending through toroidal ground fault sensing coils, and to insulating barriers for such bus bars.
2. Background Information
There is a growing demand today for circuit breakers for residential and light industrial and commercial use which provide ground fault protection. An example of such a circuit breaker is disclosed in commonly owned U.S. patent application No. 676,150, filed on Mar. 27, 1991. The ground fault detector in this circuit breaker utilizes two toroidal coils as transformers laterally spaced from one another. Both the line and neutral conductors are passed through the toroidal coils to form the primaries of the two transformers. A test lead also passes through one of the toroidal coils.
These residential and light commercial and industrial circuit breakers are designed for installation and standardized load centers and panel boards, and therefore, the space available within the circuit breaker having for the ground fault detector is limited. In order to increase the rated capacity of such circuit breakers provided with ground fault protection, commonly owned, concurrently filed U.S. Patent Application entitled Ground Fault Circuit Breaker with Flat Bus Bars for Sensing Coils, Ser. No. 07/943,801, discloses the use of flat bus bars as the line and neutral conductors passing through the toroidal coils. This co-pending application proposes insulating the bus bars from each other and from other components in the circuit breaker by coating the bus bars with an air dry insulating enamel.